Data and Code Associated with Sauve et al. Evol Letters

Included is the dataset used to measure selection gradients for mass and wing length across the ontogeny of nestling black-legged kittiwakes on Middleton Island, Alaska.

Each .csv file includes the following variables for age specific observations of nestling black-legged kittiwakes. The number after ALL indicates the age observations were taken and a number 1 following the age is the dataset that includes environmental predictors. For example hatching masses are all included in the ALL0.csv and age 5 masses are all included in the ALL5.csv. ALL01 is the file that includes environmental predictors for survival from age 0 days (hatching) to age 5 days. ALL051 would be the file that includes environmental predictors of survival from age 5 days to age 10 days. 

- Year: indicates the year of measurement

- Treatment: indicates the food supplementation treatment of the nestling observations were recorded for. fed equals food supplemented and unfed equals non-food supplemented.

- Rank: indicates that hatching rank of the nestling. a equals first hatched and b indicates second-hatched

- Age: indicates the age of mass and wing-length measurement

- Weight: The mass measurement in grams

- Wing: The wing length measurement of a nestling in millimeters

- Date: indicates the calendar date for the measurements

- GrowRefDate: indicates the date 40 days after the hatching date

- Surv0: indicates whether or not the nestling survived to the next age category. 0 indicates death and 1 indicates survival

-Weight2: The mass of the nestling mean centered and scaled to units of standard deviation 

- Wing 2: The wing length of the nestling mean centered and scaled to units of standard deviation 

CSV files ending in 1 include environmental data

- pdo1: Pacific decadal oscillation during the current breeding season

- pdo2: Pacific decadal oscillation from two years prior to the breeding season

- AirWin: Minimum air temperature during the breeding season in degrees celsius

-SSTWin: Average sea-surface temperature during the breeding season

See the below references for details on the environmental variables

Sauve, D., Charmantier, A., Hatch, S. A., & Friesen, V. L. (2022).Environmental conditions variably affect growth across the breeding season in a subarctic seabird. Oecologia, 198, 307–318

Whelan, S., Hatch, S. A., Gaston, A. J., Gilchrist, H. G., & Elliott, K. H. (2022). Opposite, but insufficient, phenological responses to climate in two circumpolar seabirds: Relative roles of phenotypic plasticity and selection. Functional Ecology, 36,1782–1795.

The RMarkdown file includes code to run the models of selection in the manuscript.